1. Field of the Invention
The present invention relates to a chassis for endless track-type vehicles with superstructures for implements and/or tools. At least a pair of essentially horizontally cantilevering support beams are provided on both sides of the chassis. The support beams extend parallel to each other and crawler track supports are slid onto the support beams. The crawler track supports are mounted so as to be slidable relative to the support beams in order to change the width of the endless track-type vehicle.
2. Description of the Related Art
Chassis for endless track-type vehicles are known in various shapes and configurations. The superstructures are single-piece or multiple-piece jibs on which may be arranged excavating tools or the jibs are used together with lifting tools or the like. However, the type of superstructure for the vehicle is not significant in connection with the present invention and, therefore, will not be discussed in detail hereinbelow.
The chassis for endless track-type vehicles have substantial widths which depend on the load-bearing capability of the superstructure. Traffic regulations concerning these types of vehicles usually provide that certain widths may not be exceeded when the chassis of the endless track-type vehicle is to be transported on a flat-bed truck or trailer from one location to another on public roadways. Otherwise, it would become necessary to carry out special transports with escort vehicles which are complicated and expensive and require permits. On the other hand, during operation of such endless track-type vehicles which requires substantial operating forces by the implements mounted on the vehicle, it is desirable that the base area of the vehicle is as large as possible, so that a high tilting moment of the entire arrangement can be achieved.
In order to take into account the contradictory requirements described above, chassis of the above-described type were designed and manufactured in such a way that the chassis could be adjusted to change the width of the caterpillar-type vehicle. For this purpose, the support beams which support the crawler track supports are constructed as longitudinally adjustable telescopic members. However, the telescopic members are of complicated construction, while still only permitting an extension of the crawler track support to a limited extent.